1. Field of the Invention
This invention relates to a strapping machine, particularly to one usable for strapping various sizes of storage boards, and its strapping operation is simple and fast by means of an expand-and-constrict style band-guiding device for a strapping machine.
2. Description of the Prior Art
In factories, warehouse industries, transportation industries, goods or mechanical components or parts are transported and stored on storage boards by utilizing lift trucks, and during transporting processes, cartons of goods or the like are generally bound on storage boards, as they are liable to sway, loosen, or fall down.
However, conventional strapping machines have a body, a strap band reel, and a band moving device to send the strap band on the reel to a guide rail of a guiding device, and the guide rail is located at the lower portion of the body, normally collapsed vertically onto the body, and swung down to be inserted under a storage boards so as to let the strap band guided by the guide rail to the rear side of the storage board, so a worker to catch the strap band and continue to perform the strapping operation. Some machines have its guide rail fixed immovable and then the strap band is guided by a drive device into the guide rail or extend outward to the rear side of a storage board.
But the conventional strapping machine uses whether a swingable guide rail or an extensible guide rail, and its length is constant, unchangeable and collapsible in the machine body, so its length is limited accordingly. Therefore, when a storage board is longer than the guide rail, the strapping machine cannot be applied. As to the swingable guide rail, when the strapping machine finishes strapping operation once, it has to retreat to let the guide rail completely separate from the storage board so the strapping machine may be turned its direction laterally for another round of operation. Otherwise, the strapping operation is impossible to go on, and it should be very inconvenient, and also requiring a large space for doing so.